Telephone-exchange system



J. L. WRIGHT.

TELEPHONE EXCHANGE SYSTEM.

APPLICATION FILED OCT; 21. 1915.

1,330,226. Patented Feb. 10,1920.

WITNESSES. lllll/f/VTUH M fol/W I J. L. WRIGHT.

TELEPHONE EXCHANGE SYSTEM.

APPLICATION FILED 0C T. 21, l9l5.

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J. L. WRIGHT.

TELEPHONE EXCHANGE SYSTEM. APPLICATION FILED ocT. 2I, I915.

' 1,330,226. Patented Feb. 10,1920. I

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WITNESSES. INVE/VTUR M A Y W W JOSEPH Ii. WRIGHT, OF CLEVELAND, OHIO, ASSIGN'OR T WESTERN ELECTRIC COMPANY,

INCORPORATED, OF NEW YORK, N. Y., A CORPORATION OF NEW YORK. I

TELEPHONE-EXCHANGE SYSTEM.

Specification of Letters Patent. Patented Feb. 10, 19 20.

Application filed October 21, 1915. Serial No. 57:055.

State of Ohio, have invented certain-new and useful Improvements in Telephone-Exchange Systems, of which the following is a specification.

My invention relates to telephone ex change systems. The obj ect of my invention is to produce a system requiring a minimum amount of apparatus of the simplest type for effecting connections between lines of calling and called subscribers.

Another object of my invention is to provide quick and eiiicient method of-operation.

The operators at the central station are provided with answering and calling sets of keys, used for-controllingthe interconnection of subscribers lines. These keys take theplace of the ordinary plugs and cords used in so-called manual exchanges. operator is provided with a number of sets of answering and calling key-sets to enable her to handle the originating calls without loss of time.

In addition to the key-sets the operator is provided with a group-or bank of signal lamps, one being individual to each line appropriated to her position.

In the so-called semi-automatic systems the operator is usually provided with a sending device for controlling step-by-step switching mechanism for extending connections from calling to called subscribers lines.

WVithimy invention the cords or plugs of the so-calledmanual systems are dispensed with, as well as the step-by-step mechanism and sending devices used 1n semi-automatic systems.

Each set of answering and calling keys is provlded with a set of what are termed tens-relays. Each tens-relay of a set preferably contains the terminals of ten subscribers lines. By providing ten relays for each set, access is given to one-hundred lines. Opposite sets of contacts in these relays are connected to contacts in what are termed units-keys. These contacts are multipled into each tens-relay of its set. The tens-relays are controlled by a separate set of tens-keys or but-tons. In order to operate a particular tens-relay a correspond- The ing tens-button is depressed thereby energizing the selected relay. I

The particular units-button is then depressed, which connects the link or trunk to the selected line through the contacts of the operated tens-relay and contacts of the units-button.

The grouping of tens-relays and unitsrelays are fully disclosed in Patent No.

1,091,193, to-E. E. Clement, March 24, 1914:. I dispense entirely with the use of the units relays, however, by substituting units-keys or buttons.

As each end of the link or connecting circuit is provided with a set of tens and unitsbuttons and cooperating tens-relays, the operator by depressing the properbuttons can interconnect any line over the link circuit.

revision is made to provide automatic, disconnect or release of the buttons when either the calling or called subscribers hang up their receivers, thus dispensing with su pervision by the. operator.

My invention is illustrated in the accompanying drawings, wherein:

Figure 1 shows a calling subscribers line equipment, a set of answering buttons and cooperating relays.

Fig. 2 shows a link or connecting circuit. Fig. .3 shows the equipment of a called subscribers lineequipment, a set of calling but tons and cooperating relays.

Referring to Fig. 1, the subscri'bers equipment at A comprises apparatus usual in common battery systems. The line wires terminate'in a l1ne relay D through the contacts of a cut-off relay C. The set of tens-buttons are shown at T and a set of units-buttons at U. These buttons or keys are of the usual locking and indicating type. When a button in one row is depressed it will releasethe button formerly keys is provi ed with a release magnet which, upon operating, moves the latch,

thereby causing the automatic restoration of the keys. Keys operatedin this manner are depressed. Each strip of p contacts. (ontacts which engage corre sponding contacts leading to the lines are multipled as shown. The first set of these contacts of each relay are connected in multiple and also connected to contacts in No. 1 unit-button. No. 2 set of contacts in each relay are connected in multiple and also connected to' contacts in No. 2 unit -button. This manner of connecting the buttons and contacts of the relays is continued throughout the set. V f

In case each operator-is provided with ten sets of answering and calling buttons, then the line contacts of the tens-relays will be multipled as disclosed in the Clement Patent No. 1,091,193. The line contacts of the answering relays in the present instance will also be connected in multiple to contacts of the tens calling relays so as to enable the operator to effect connection with any line through the callingset of relays, shown in Fig. 3.

, Each line relay '1) will control an individual signal lamp 0. If the lines are formed into groups of one-hundred, then there will be one-hundred of these signal lamps before the operator.

Referring to Fig. 2, thetip and sleeve conductors 4+6, 2224 are separated by the condensers 5 and 23 as shown.

The tip conductor 4, sleeve conductor 22 and conductor 33 are connected to contacts in each of the units buttons in the row V.

'. Battery supply is furnished to the calling subscriber through thewindings of relay F and retardation coil S. l Battery supply is furnished the called subscriber through the windings of relay H and retardation coil V.

Relay J is the ringing relay. controlled by the constantly rotating commutator W.

K is the test relay for determining the condition of the called line.

The equipment illustrated in Fig. 3 is identical with that of Fig. 1' and need not be described. The unit set of buttons UU is, however, provided with a set of contacts indicated at X (Fig. 2). The contacts X are closed when anyone of the units buttons is depressed to its extreme or near extreme position. These contacts may be controlled by the latch bar common to all the keys in the strip. When pressure is removed from No. 22, depresses No. 2 button in the royt T and N o. 2 button in the row U. The op;- eration of No. 2 button in the row T pletes the circuit of the tens-relay 20 thereby connecting the ten lines in the group containing the calling line to themultipled contacts leading to the contacts in the buttons U.. As button No. 2 in the row U is The operation of relay C discon- The operator upon learning the number desired, which we will assume to be 111, depresses No. 1 button in the row TT, and No. 1 button in the row UU. The operation of the button TT operates relay 110, thereby connecting the group of ten lines containing the called line to the contacts of the buttons UU. As No. 1 button is depressed it, therefore, follows that onlyone line, namely, 111, will be connected to the called end of the link or connecting circuit (Fig. 2).

In depressing the button in the unit row UU the contacts springs X are closed thereby operating relay L. The operation of this relay disconnects battery from the winding of relay H and ground from the winding of relay ,V, andalso disconnects relay I from conductor 51. and in its place connects the test relay K. This conductor 51 extends to the winding of the cut-off relay of the called line, and if the called line is busy battery will be connected to 'conductor 51 through the winding of some other relay 1. fthe called line tests busy. relay K will become operated and complete the circuit of release magnets MM and NN of the tens and units keys in multiple by the following path: ground, contacts of relay K, 39, windings of magnets MM and NN to battery B. The operation of these magnets cause the restoration of No. 1 keys in the tons and units rows. The restoration of these keys indicates to the operator that the called line is bus The operation of relay K also connects t 1e busy tone signal to the sleeve conductor 36, which notifies the calling subscriber that the called-for line isbusy. Relay K when operated is kept locked to battery through the, contacts of relay F controlled by the calling subscriber.

The calling subscriber upon replacing his receiver after recei 'ing the busy indication causes the decnergi'zatlon of relay F. This I relay in restoring unlocks relay K and completes the circuit of the release magnets M and N of the keys U and T in multiple by the following path: ground, contacts of relay E, 35, contacts of relay F, 36, winding of magnets M and N to battery B. The operation of these magnets causes the restoration of the depressed buttons in their respective rows. The'restoration of the buttons causes the release of relay 20 and of relays C and E. i

In case the called-for line is not busy, then relay I will'be placed in series With the cut-off relay of the called line. .The operation of the cut-off relay disconnects its associated line relay and connects the line conductors to the line extensions leading to the ground, contacts of relay H, winding ofrelay G, 43, contacts of rela I to battery B. The operation of relay prevents the operation of relay J and also places the control of the release magnet MM and NN un-' der control of the called subscriber. The relay G is provided with a locking contact and after being operated by relay His there after under control of relay I. V

. At the termination of the conversation the calling subscriber replacing his receiver causes the deenergization of relay F thereby causing the restoration of the buttons in the rows T and U in the manner previously described. a

The called subscriber replacing his receiver causes the denergization of relay H, which. in restoring completes the oircult of magnets MM .and 'NN by the. following path: ground, contacts of relay H, 41,- contacts of relay G, 38, contacts of relay K, 39, windings of magnets MM and NN to battery B. The operation of these magnetscauses the restoration of the keys TT and UU. The restoration of the key TT releases relay 110, and also severs the connection between relay I and the cut-oil relay of the called line.v Relay I restorin removes battery from the winding of re ay thereby causing it to restore.

In case the called-for subscriber does not answer then the calling subscriber controls the release of the buttons UU and TT by energizing magnets MM and NN in multiple by the following path: ground, contacts of relay E, 35, contacts of relay F, 36, 37,

contacts of relay G, 38, contacts of relay K,

39,. windingsof magnets MM and NN to battery B. The operation of these magnets causes the restoration of the keys in the rows TT and UU and the operation of the .magnets M and N'in the rows T and U in to note the position or number of the signal lamp and then depress the answering button corresponding to the number indicated and then after ascertaining the number desired depress corresponding calling buttons. At ter once establishing a connection there is no necessity for supervision, as the calling and called subscriber are automatically released upon the replacing of their receivers.

While I have illustrated but one operators connecting trunk or link circuit, each end provided with a set of keys, it naturally follows that each operator will be provided with enough connecting circuits to care for the traflic at her position.

I preferably arrange a group of onehundred line signals at each operators position and in case there are several hundred lines terminating in the exchange to which access 'must be given through the calling end of the trunk it is necessary to provide extra sets of tens or hundreds keys or buttons. For each one-hundred lines there will be ten buttons, as shown at 'IT controlling ten relays. I

In case there are three-hundred lines in the exchange then each outgoing or calling end of the trunk will be provided with thirty buttons TT and thirty relays controlled thereby. The units keys UU will be multipled into corresponding contacts of the thirty relays. Of course the line contacts of the three-hundred lines will be multipledvinto each set of relays at every operators position which is controlled-by the buttons TT.

The only niultipled connections extending from one connecting trunk to another are the line contacts of the called lines.

In case the rows of buttons TT are arranged side by side then each one of the three rows can be provided with a resetting button which serves to trip the latch and release the buttons in its particular row.

In place of using rows of buttons a rotatmg switch may be provided. This switch can be rotated by the operator to the proper position and tripped .by a release magnet to restore it to its normal position or supervisory signals may be associated with the connecting links as in the ordinary manual systems.

With this arrangement the operator can control the release of the switches or buttons at will. v

Having thus described myinvention, what I desire to secure by Letters Patent is: 1. In a telephone exchange system, the combination with calling and called subscribers lines, of a link circuit, a set of relays and keys individual to said link for con necting a calling line to said link, and a corresponding set'of relays and keys for also connecting a called line to said link, said relays and keys serving as a sole means for connecting said line and link circuit.

2. In a telephone exchange system, the

- combination with calling and called subcombination with a plurality o scribers lines, of a link circuit, a set of relays and keys individual to the answering end of said link, and a corresponding set of relays and keys individual to the calling end of said link, means for operating said relays and keys for connecting a calling line to the answering endof the link and for connecting a called line to the calling end of said link for conversational purposes, said relays and keys serving as a sole means for interconnecting said line with said link circuit.

3. In a telephone exchange system, the

combination witha plurality of subscribers" lines, of a link circuit, a set of tens-relays and a set of cooperating units-keys associated with each end of said link circuit, means for operating said keys and relays for interconnecting said lines. Y

4. In a telephone exchange s stem, the electrical circuits, of a link circuit, a set of relays and a set of cooperating keys individual to each end of said. link circuit, means for operating said keys and relays for interconnecting said electrical circuits over said link circuit, said relays and keys serving as a sole means for interconnecting said electrical circuits over said link circuit.

5. In a telephone exchange system, the combination with a-calling and 9. called subscribers line, of a link circuit, a set of cooperating relays and keys associated with the answering end of said link, and a corresponding set of cooperating relays and keys associated with the calling end of said link, restoring means for each set of keys, means for operating said relays and keys for connecting a calling line to the answering end of the link and for connecting a called line to the calling end of the link, means controlled by the calling and called lines for opline when completed extending contacts of said relays and keys.

with the calling end of said link, means controlled by one set of keys for operating the relays and means controlled by the other set of keys and contacts of said relays for connecting the calling line to the answering end of the link, and for connecting the called line to the calling end of said link.

7. In a telephone exchange system, the combination with a called subscribers line, of a link circuit, a, set of relays and keys associated with said link, means for operating said relays and keys for connecting said line to said link, additional means associated directly with said keys for determining whether the called line is busy or idle.

8. In a telephone exchange system, the combination with a plurality of subscribers lines, of a link circuit, a set of relays and two sets of'keys assoclated with said link, means controlled by one set of keys for operating said relays, means controlled by the other set of keys for connecting said link to any one of said lines, said connection ex- 'tending through the contacts of the other said set of keys.

9. In a telephone exchange system, the combination with a plurality of subscribers lines, of a link circuit, a set of relays and keys associated with said link, means controlled by some of the keys for operating said relays, and means controlled through the contacts of other of said keys and con tacts of said operated relays for connecting any line to said link, the connection of said through the 10. In a telephone exchange systemythe combination with a plurality of subscribers lines, of a link circuit provided with a set of relays and keys, some of the keys having contacts connected to said link and other contacts connected to contacts in said relays, said relays being provided with cooperating contacts connected to said lines, means controlled by the other of said keys for operating said relays to connect said lines to said link, the connection of said lines to said link extending through the contacts of said relays and keys. I

11. In a telephone exchange system, the

- combination with a plurality of subscribers link, said lines when connected to said link extending. directly through the contacts of said relays and said keys.

12. In a telephone exchange system, the

combination with a called subscribers line,

of a link circuit, a set of relays and keys associated with said link for effecting connection with said lines, of a test relay associated with said link, means associated with said keys when connection is effected with said line for directly connecting said test relay thereto for determining whether the said line is busy or idle. 13. In a: telephone exchange system, the combination with a called subscribers line, of a link circuit, a set of relays and keys associated with said-link "for effecting contacts when interconnecting said link with said line for determining whether the line is busy or idle.

15. In a telephone exchange system, the combination of a plurality of subscribers lines,3of signals individual to said lines, a link circuit common to said lines, a set of relays and a set of cooperating keys associated with said link circuit for directly interconnecting with any of said lines in response to said signals, releasing means for said keys and relays, said releasing means being controlled by said lines.

16. In a telephone exchange system, the combination of a plurality of subscribers lines, a link circuit, aset of relays and aset of cooperating keys individual to each end of said link circuit, means for operating said keys and relays for interconnectingsaid lines.

17. In a telephone exchange system, the combination of calling and called subscribers lines, of a link'circuit, a set of relays and keys individualto the answering end of said link, a corresponding set of relays and keys individualto the calling end of said link, means controlled by one of said keys for operating therelays to connect the calling lines to one end of said link and means controlled by the other set of keys for operating the other set of relays for connecting the called lines to the opposite end of the link.

18. In a telephone exchange system, the

combination of a called subscribers line, of a link circuit, a set o'f relays and keys associated with said link for effecting connection with said line, a test relay associated with said link, releasing means for said keys, means associated with-said keys when con nection is effected with busy lines for operating said test relay for rendering operable said releasing means. I

'19. In a telephone exchange system, the combination of a plurality of subscribers lines, of a link circuit, a set of relays and a set of cooperating keys associated with each end of said link circuit, means for operating said keys and relays for interconnecting said lines, and means controlled over said lines after interconnection for releasing said keys and relays.

20. In a telephone exchange system, the combination of a plurality of subscribers lines, of a signal individual to each of said lines, a plurality of link circuits,a set of relays and a set of cooperating keys associated with said link circuit located at an op'er'ators position, means controlled by said operator for connecting any one of said lines inresponse to said signals to any one of said link circuits, signals for said link circuits, said. signals serving to indicate the condition of the connection when established.

21. In a telephone exchange system, the combination of a plurality of subscribers lines, of a plurality oflink circuits, a set of relays and cooperating keys associated with each end of said link circuit, an operators position, means controlled from said position for operating said keys and relays of 1 any one of said link circuits for interconnecting said lines.

22. In a telephone exchange system, the combination of a plurality of subscribers lines, of a plurality of link circuits, a set of relays and cooperating keys associated with each end of said link circuit, an operators position, means controlled from said posi- 110 tion for operating said keys and relays of any one of said link circuits for interconmeeting said lines, releasing means for said .keys and relays, said releasing means con .trolled by said lines after interconnectlon.

23; In a telephone exchange system, the combination of, a plurality of subscribers lines, a link circuit, aset of keys associated with each. end of said link circuit, means controlled by said keys for interconnecting said lines over said link circuit. v

24. In a telephone exchange system, the combination with a plurality of subscribers" li es, a link circuit, a set of relays and a cuits, a link circuit, a set of relays and a set of cooperating keys individual to each end of said link circuit, means controlled by said relays for interconnecting said electrical circuits over said link circuit.

26. In a telephone exchangesystem, the combination. of a plurality of electrical cir cuits, a link circuit, a set of relays and a set of cooperating keys individual to each end of said link circuit, means controlled by said relays for interconnecting said electrical circuits over said link circuit, a signal for said link circuit, said signal serving; to indicate the condition of the electrical circuits when so interconnected.

In testimony whereof I affix my. signature in the presence of two witnesses.

JOSEPH L. WRIGHT.

W'itnesses I ANNA MCCUNE, ADA DEHN. 

